The invention relates to a micromanipulator for the displacement of a sample carrier according to different degrees of freedom by means of displacement members mounted on elastic bellows, which participate in the transmission of the movements through a wall.
Such a manipulator can be used in a vacuum or in an ultrahigh vacuum or in controlled atmospheres.
A micromanipulator of this kind is described in U.S. Pat. No. 4,587,431. It permits of ensuring in an ultrahigh vacuum the positioning of samples before a beam. The displacement can be effected according to three orthogonal translatory movements and according to two rotations: the rotation of the sample itself with respect to the axis perpendicular to its plane and a rotation of inclination of this plane with respect to the beam. In order to obtain the transmission of the commands between the zone at atmospheric pressure and the zone in an ultrahigh vacuum, elastic bellows are used. For the transmission of the translatory movements of the sample, the bellows concerned are moved by transmission means, which perform a translatory displacement. For the transmission of the rotary movements of the sample, the bellows concerned are moved by rotation means, which in the zone in an ultrahigh vacuum are transmitted by means of a so-called "pig-tail device".
However, such a micromanipulator is voluminous. Moreover, the bellows transmitting the rotary movements operate in the torsional mode, which can be detrimental to their operation. In fact, such repeated actions render the bellows brittle, which can then present microleaks or larger leaks, which results in that the lifetime of these bellows is limited.
The problem to be solved by the invention is to provide a micromanipulator which is as compact as possible, which offers several degrees of freedom in translation and/or in rotation with high amplitudes and a high precision and which transmits the initial commands while avoiding to exert torsional forces on the bellows. It must ensure a very stable position of the sample and it must be readily controllable from the outside in order to permit a programmable operation.